Mine was triggered by my pregnancy/birth/sleep deprivation after...I'm not sure what but probably a combination.
Here is the link I put together. It's kind of geared toward kid stuff but the mitochondrial information is adult pertaining as well and is in the middle. This is probably the single most common metabolic condition and it can and does have adult onset. Many women find they get sicker after pregnancy--the stress that puts on the body does mitochondrial damage and if you already have an underlying issue can tip it over to symptomatic or worsen already present symptoms. That's what happened to me (dramatically worsened stuff that I think had been there for quite a while). I just got sicker and sicker. I had really low coq10 levels (my son had really low carnitine/he has the same thing). When I corrected that it helped a lot especially w/the fatigue.
http://www.mothering.com/discussions...d.php?t=734501http://www.umdf.org/site/c.otJVJ7MMI...aminsCofactors The stuff listed in the first tier is what I'm doing except I am not doing carnitine because my levels are really high already and I want to save the expense (my son is on all of the things listed). The coq10 used is not the kind at the local drugstore. It's sold by epic4health and produced by Tischon corp. It is used in clinical trials and works much, much better than stuff you can get anywhere else. It's the kind used for this and other conditions that respond to coq10. If you did acyl carnitine (doses listed in second tier) you wouldn't need a script to do any of this. But if you have low carnitine you'd want carnitor itself.
If you want to look into this possibility one way you can do it is find a doctor to run a metametrix urine profile on you. It picked up my son's issues in this area though it's not a formal metabolic lab. We already knew my son had this disorder and ran metametrix for other stuff but it was so interesting to get the results and see how it matched his formal metabolic labs (more invasive). Have a doctor run a coq10 and carnitine level to see if you're deficient in either of those (you don't have to be to have this disorder but if you are deficient correcting the issue will often result in improvement). I'm doing pretty well now and so is my son. Kids who present early in life aren't going to look like adults with this and severity even among those with the same mutation varies considerably. How sick you are depends on a lot of things including how many diseased mitochondria a person has.
Let me know if this seems possible for you and you have any questions at all for me. I sort of hope for you this is it because I've found so much help in treatment and I'd wish the same for you. I did want to mention I also had sleep apnea and I don't fit the profile of a sleep apnea patient.
and it makes it a drag to go to work on "bad days" blah.
It is hard. It's hard to live sick and tired (scratch that downright exhausted). And those who haven't been there just can't understand. 
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